Add 1/42 and 40/21, Solve 1/42 + 1 19/21 as a fraction

Add 1/42 and 40/21

1^st number: 1/42, 2^nd number: 1 19/21

1/42 + 40/21 is 27/14.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 21 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 42 × 1 = 42,
1/42 = 1 × 1/42 × 1 = 1/42
Likewise, for the 2nd fraction, since 21 × 2 = 42,
40/21 = 40 × 2/21 × 2 = 80/42
Add the two like fractions:
1/42 + 80/42 = 1 + 80/42 = 81/42
81/42 simplified gives 27/14
So, 1/42 + 40/21 = 27/14
In mixed form: 113/14

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